Internal-combustion engine



Nov. 23 1926. Q 1,608,322

K. O. KELLER INTERNAL COMBUSTION ENGINE Filed April 20, 1925 ll lhllll lullmllqp III mvuxom Patented Nov. 23, 1926.

UNITED STATES PATENT 0 1,608,322 FICE.

KARL OTTO KELLER, OF SUNDERLAND, ENGLAND, ASSIGNOR OF ONE-HALF TO ROBERT PILE DOXFORD, OF SUNDERLAND, ENGLAND.

INTERNAL-COMBUSTION ENGINE.

Application filed April 20, 1923, Serial No. 633,469, and in Great Britain May 30, 1922-.

This invention is for improvements in or relating to compressed-air inlet-valves for internal combustion engines, and has for its object to provide an'improved method of operating them.

Heretofore, the valves foradmitting compressed air to the cylinder of an internalcombustion engine for starting the engine have been operated directly through levers from a cam-shaft situated near and alongside the working-cyIinders-,--er alternatively, these valves have been operated by means of compressed air acting on' -a piston which operates the valve-spindle through a rock ing lever.

The present invention is applied to engines of the type in which the fuel is supplied to the cylinder under high pressure, and in which the fuel system is maintained under a steady pressure at all times, that is to say, a pressure which does not materially vary stroke by stroke of the engine; according to this invention the compressed air inlet-valve is operated hydraulically by the fuel oil which is under high pressure. Preferably the controlling device for the hydraulically-operated valve is situated remotely from the valve which it controls, so that it] can be placed in any convenient situation, and theonly mechanism on or ad acent to the cylinder is the compressed-air valve, and

a hydraulic piston which operates it. The hydraulic piston may be directly connected to the valve so that it is only necessary to provide pipe connections from the said hydraulic piston to the controlling device and the high-pressure fuel-oil system.

Where the main pump for maintaining the high pressure in the fuel-oil system is driven ythe engine, an auxiliary pump is provided to serve as a stand-by for the main pump, and also for charging up the .system previous to starting the engine, if such charging is necessary.

In the accompanying drawing Which illus trates this invention diagrammatically, a cylinder of an internal-combustion engine is indicated at 10 with a piston 11, connectingrod 12 and crank-shaft 13. A compressedair supply-pipe 14: communicates with the interior of the cylinder 10 through a port controlled by a valve 15. The valve is shown as of the balanced type with a spring 16 holding it in its closed position. A hydraulic piston 17 engages the valve so as it can open communication between inthe form of a valve-chest having pipeconnect1ons'19 as aforesaid, 21 to the highpress'ure fuel-oil system and 22 to exhaust. Within the valve-chest 20 there is mounted a valve 23 so constructed and arranged that the pipeconnections 21 and 19, or alternatively, bev tween the pipe-connections 22 and 19. In the first case, high-pressure oil is admitted to the pipe 19 to move the piston 17 and thereby open the valve 15, and in'the latter case, the pipe 19 is open. to exhaust to relieve the pressure therein so that the spring 16 can return the parts to their normal posi tion, closing the valve 15. The valve 23 is operated by means of a rocking-lever 2 1 which is in turn actuated by a cam 25 and shaft 26 driven in any convenient manner from the engine crank-shaft 13, so that the valve 15 is open to admit the compressed air at a suitable time in each stroke of the en- 95 gine. The lever 24.- is provided with an adjustable fulcrum 27, so that it can be brought" into or out from operative engagement with the cam 25. The operative connection betweenthe shafts 13 and 26 is indicated diagrammatically in chain-lines by the bevelwheels 28 and 29.

It will be understood that the accompany" ing drawing is purely diagrammatic, and that the invention is not limited toany particular construction of hydraulicdevice or air-starting valve,'since it will be obvious that-these may be of any known or desired form.

WVhat I claim as my invention and desire 1m to secure by Letters Patent is 1. The combination'with a high pressure fuel-oil engine having a source of high pressure fuel supply therefor and having an air inlet-valve, of a pressure operated actuating 0 ating pressure thereto, an'engine operated valve in the said conduit for intermittently establishing communication between the source of high pressure fuel supply and'the pressure operated air-valve actuating means, and means for rendering the engine operated valve inoperative.

2. The combination with a high pressure fuel-oil engine having a source of high pressure fuel supply therefor and having a balanced air inlet-valve, of a pressure operated actuating means for the inlet-valve, the said means comprising a hydraulic piston operatively engaging the air valve, a conduit connecting the high pressure fuel sup ly with the said actuating means for supp ying an operating pressure thereto, an engine operated valve in the said conduit for intermittently establishing communication between the source of high pressure fuel supply and the pressure operated air-valve actuatin means, connection between the en ine an the valve in the conduit being eflected by means of a cam-actuated lever, and means for renderingthe said cam-actuated lever inoperative.

In testimony whereof I aflix my signature.

KARL OTTO KELLER. 

